Electrocoat finishing systems are typically warm, damp places and undesirably provide conducive conditions for microorganism growth. Once microorganisms colonize on an electrocoat system, removing the contamination is very difficult and can be quite costly. High levels of contamination in the system can lead to increased reject rates for parts or operational issues with the finishing system.
Various techniques have been implemented in the industry to combat microorganism growth in electrocoat tanks and equipment. Power washing and other physical removal methods have been used, for example. Other conventional methods include chemical-based treatments, such as the use of biocides, solvents, halogen-based chemicals (e.g., Cl, Br,), and metal-containing (e.g., Cu, Ag) compounds. Existing methods for cleaning have several drawbacks. Some of the cleaning chemicals are toxic and/or expensive, the treatments tend to be very labor intensive, many of the contaminated areas cannot be accessed easily, and effectiveness cannot readily be gauged until days after the process is complete. Furthermore, regulatory agencies continue to add or revise laws and guidelines relating to the amounts of solvents allowed to be released into air and water waste streams. Thus, practitioners in the electrocoating industry are encouraged to develop more “environmentally friendly” processes. This, however, leads to increased conditions for microorganism growth.
What is needed is a method for removing microorganism growth from electrocoating equipment that can be easily practiced and has minimal negative impact on the environment.